Salt and Cream of Tartar affecting foaming of egg whites during whipping

From: Nathan A Unterman
To: Heshy Weiner Date: Wed, 12 Mar 2014 07:33:39 -0500
Subject: Salt, egg whites, Cream of Tartar

Salt increases the whipping time of the egg whites and decreases the stability of the foam. This is because salt dissolves into positive and negative ions. These ions bond with proteins, which disrupts the foam from forming. To protect the foam, salt is normally added after the whites have been beaten to the foamy stage.

Acids (vinegar, lemon juice, cream of tartar,etc) are also added after the foamy stage has been reached because they delay foam formation. Acids are useful because they stabilize the foam. Acids decrease the pH, which reduces the ability of the proteins to coagulate.

Cream of tartar: Potassium bitartrate, also known as potassium hydrogen tartrate, with formula KC₄H₅O₆, is a byproduct of winemaking.

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Nathan A. Unterman